Have you ever seen the solar system glow? For the next couple of weeks, skywatchers in the Northern Hemisphere can see the zodiacal light, an eerie triangular glow that appears in the east before sunrise. Known as the “false dawn,” it looks like light pollution but is actually sunlight scattered by dust spread through the inner solar system. It’s something that requires patience and inky black night skies — but those taking camping and RV trips at this time of year are in prime position.

Zodiacal light is a faint, diffuse cone of white light extending upward from the horizon along the ecliptic — the apparent path of the sun through the sky, which is also roughly where the moon and planets are found.

The glow comes from sunlight scattering off particles of interplanetary dust concentrated around the plane of the solar system. It’s a solar-system-scale version of sunlight streaming through a dusty room, catching the particles at the right angle.

Don’t confuse it with the “false dusk,” the name given to zodiacal light visible in the west after sunset around the March equinox.

Zodiacal light gets its name from the zodiac because the ecliptic passes through the zodiacal constellations — also known as astrological star signs.

When To See The ‘False Dawn’

September is one of the best times of year to see the zodiacal light from the Northern Hemisphere because the ecliptic rises steeply from the eastern horizon before sunrise around the fall equinox. That’s why September’s zodiacal light is called the “false dawn.” For the best chance this month, begin looking during the moonless mornings after the new moon on Sept. 10 and continue through roughly Sept. 24, before moonlight begins to brighten the predawn sky. Get to your observing location about 90 minutes before sunrise and look east as astronomical darkness gives way to twilight.

How To See Zodiacal Light

Darkness is everything. Zodiacal light is faint, so you’ll need to be well away from artificial light, with a clear, unobstructed eastern horizon and preferably no clouds or haze. Use a light pollution map to find an extremely dark spot. Look for a large, softly glowing pyramid extending diagonally upward from the eastern horizon. It can resemble the glow of a distant city, but it stretches upward along the ecliptic rather than staying concentrated near the horizon. Give your eyes at least 20 minutes to adjust to the darkness, and try using averted vision — looking slightly to one side of the glow rather than directly at it.